Решение:
a) -(18 - 6) = -18 + 6 = -12
б) -6 + (-2 + 7) = -6 + 5 = -1
в) -(-9,1 - 1,1) = -(-10,2) = 10,2
г) -(3$$\frac{11}{18}$$ - 5,7) + (4$$\frac{17}{18}$$ + 2,3) = -(3$$\frac{11}{18}$$ - 5$$\frac{7}{10}$$) + (4$$\frac{17}{18}$$ + 2$$\frac{3}{10}$$) = -3$$\frac{11}{18}$$ + 5$$\frac{7}{10}$$ + 4$$\frac{17}{18}$$ + 2$$\frac{3}{10}$$ = (-3$$\frac{11}{18}$$ + 4$$\frac{17}{18}$$) + (5$$\frac{7}{10}$$ + 2$$\frac{3}{10}$$) = 1$$\frac{6}{18}$$ + 7$$\frac{10}{10}$$ = 1$$\frac{1}{3}$$ + 8 = 9$$\frac{1}{3}$$